head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is execution, and it is a single point.

Execution · Practiced Mastery
Robot-dinosaur hunting that rewards weak-point study and ranged precision.

Optimization · Practiced Mastery
A storybook underwater metroidvania about a girl piloting a homemade submarine to find her father.
Horizon Zero Dawn leans Execution (Practiced Mastery); Song of the Deep leans Optimization (Practiced Mastery).
Horizon Zero Dawn leans a little harder on execution, though the gap is small.
Horizon Zero Dawn
Bow aiming and dodge timing matter.
Song of the Deep
Gentle submarine handling and claw manipulation
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Horizon Zero Dawn
Machines follow fixed patterns, not adapting.
Song of the Deep
Scripted sea creatures
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Horizon Zero Dawn
Some loot and patrol randomness.
Song of the Deep
Unknown undersea map first dive
Song of the Deep leans a little harder on optimization, though the gap is small.
Horizon Zero Dawn
Weak points, traps, builds fully solvable.
Song of the Deep
Environmental puzzles and upgrade routing carry the game
A matching score does not mean a matching test. Two games can both sit at 10 on execution and demand completely different things of you - which is why the reasoning above matters more than the number beside it.